Thermostatic instrument



No. 627,322. Patented :une 2o, |899.

c. unanen.

THEBMDSTATIC INSTRUMENT.

(Application led Tune '7, 1898.)

(No Model.)

i n v WITN 55555 UNITED STATES PATENT (NEIGE.

CHARLES BURGHER, OF WIN THROP, MASSACHUSETTS.

TH ERIVIOSTATIC INSTRUMENT.

SPECIFICATION forming part of Letters Patent No. 627,322, dated June 20, 1899.

' Application iiletl .Tune '7, 1898. Serial No. 682,814. (No model.)

To all whom, t 77u03/ concer/t.'

Beit known that I, CHARLES BURGHER, residing in Vinthrop, in the county of Suffolk and State of Massachusetts, have invented an .Improvement in Thermostatc Instruments,

of which the following description, in connection with the accompanying drawings, is a specification, like letters and figures on the drawings representing like parts. Y

This invention relates to a `thermostatic instrument for use in automatic fire-alarm systems, and has for its object to provide a simple and efficient instrument for the purpose specied. v

The particular features of this invention will be pointed out in the claims at the end of this specification.

Figure l represents in section and elevation one form of therm ostatic instru ment embodyingthisinvention; Fig. 2, atransverse section of the instrument shown in Fig. l, taken on theirregular line 2 2, looking upward; Fig. 3, a vertical section on the line 3, Fig. 1, looking toward the left; Figs. 4 and 5, details to be referred to; Fig. 6, a modification to be referred to, and Fig. 7 a detail to be referred to.

Referring toFig. l, A represents a base or support,of porcelain or other suitable insulating material, which is adapted to be fastened to the ceiling of a room, as by screws, (not shown,) but which may be inserted through holes ct.

The base A supports two circuit-terminals,-

shown as metal arms a a2, each comprising aVV vertical portion 2 and a horizontal portion 3, and the said terminals may be secured to the base A, as will now be described. The base A on one face has an annular ange a4, provided at substantially diametrically opposite points with slots or recesses a5, in which are secured, as by screws a6, metal arms a? a8, to which the vertical portions 2 of the terminals a a2 are fastened, as by the binding-posts o, am, to which the line-wires cl2 als are connected, as by screws a al, The horizontal portions or arms 3of the circuit-terminals extend substantially parallel with the base A and beyond a line through the center of the same, and are curved, as shown in Fig. 2, so as to leave an opening 6, and the free end of each terminal beyond the opening 6 is brought into line with its coperating terminal, but is separated therefrom, as'herein shown, so that the circuit through the thermostat is normally.

open. The free end of each terminal may vand preferably will be provided with a platinum or other contact point 7, which coperates with a like contact plate or block 8 on the other terminal.

The circuit-terminals are adapted to be electrically connected by an actuating device,

represented as a Weight Z2, provided with a stem or projection b, which extends through the opening 6 and also through an opening9 in a casing or cover b2, which fits over and is secured to the outside of the flange a4 by screws (not herein shown) or in any other suitable manner.

The weight or actuating device l) is normally held in an inactive position by fusible means, preferably solder, which is represented in Fig. l as a heavy black line b, and is employed to unite two parts b4 b5 of a support for the weight. The parts 19455 (shown in Figs. l, 3, and 5) are made in the form of small spoons or cup-shaped pieces provided with handles having holes or openings o7 forthe reception of hooks bs, attached to lugs or projections Z920, secured to the casing b2. The lugs b2@ may be of insulating material and provided with a metal screw or stem, (see Fig. 7,) which is adapted to be screwed into athreaded'hole in the casing b2. The bowls or cup-shaped pieces are fitted together and united by the fusible solder b9, and, if desired the said cup-shaped pieces may be provided with holes Z910 for the passage of the solder, which serves to rivet the pieces b4 b5 together.

By reference to Fig. 1 it will be seen that the fusible solder is separated from the bottom of the casing by an air-space, which renders the instrument very sensitive, for in case of fire the fusible solder is surrounded by heat. In some localities it is desirable to seal the circuit-terminals from the action of vcorrosive gases and moisture-as, for instance, in acid-works-and in this case I prefer to make the support for the weight as a single piece b, which is attached to the casing b2 by fusible solder D200, as shown in Fig. 6, which construction seals the opening 9 in the case '112.

In operation the Weight is normally inactive, being held up olf from the circuit-terlOO minals by its support, and the/'said terminals at such time being open', but when the temperature rises in the vicinity of Ithe instrument sufficient to melt the solder the support for the weight gives way and the latter drops by gravity, and thereby brings the terminal a2 into contact with the terminal cd and described.

2. In a thermostatic instrument, the combinat-ion of the following instrumentalities, viz: a base, circuit-terminals secured thereto on substantially diametrically opposite sides and provided with cooperating overlapping arms extended substantially parallel with said base, a casing inclosing` said terminals and provided with an opening, a weight within said casingindependent of said terminals and provided with a stem or projection extended through said opening, and a fusible support attached to said casing and normally supporting said weight above the overlapping arms of said circuit-terminals, substantially as described.

3. In a thermostatic instrument, the combination of the following instrumentalities, viz: a base, cooperating circuit-terminals attached thereto and normally inoperative, a weight to render said circuit-terminals operative, a stem or projection on said weight, a casing inclosing said terminals and provided with an opening through which said stem or projection extends, a two-part support for said stein and Weight, fusible material uniting the said parts, and lugs attached to the said casing and to which the parts of the support are connected,substantially as described.

4. In a thermostatic instrument, the combination of the following instrumentalities, viz: a base, coperating circuit-terminals attached thereto and normally inactive, a casing inclosing said terminals, an actuating device for said terminals to render them active provided with a stem 0r projection extended through said casing, and a support for said stein comprising cup-shaped parts provided with handles which are attached to the'casing, and fusible material uniting said cupshaped parts, substantially as described.

5. In a thermostatic instrument, the combination with spoons b4, b5 comprising cupshaped pieces or bowls fitted together and provided with handles, of fusible material interposed between said bowls and limiting said spoons, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

CHARLES BURGHER.

Witnesses:

JAs. II. CHURCHILL, J. MURPHY. 

